Although rare, nephropathic cystinosis is a devastating monogenic disorder leading to renal failure in the second decade of life. Fanconi syndrome, the initial renal manifestation of cystinosis in the young child, established the proximal tubule as a primary target of injury now recognized as the result of mutations in cystinosin (CTNS), the lysosomal cystine-proton cotransporter.1 A major chal...

ROW-RAMEL, FRANCOISE, FRAN~OISE CHOMETY, AND G. PETERS. Urea concentrations in hh.darj?uid and in wnal tissue of nondiuretic rats. Am. J# Physiol. 2 15(Z) : 429-438. 1968.-Concentrations of urea and of inulin or polyfructosan were measured in proximal and distal tubular fluid of nondiuretic rats (P,,,, 5.5 =t 0.6 rn~) and rats infused with small doses of urea (P,,,, 11.8 + 1.1 mM>, Papillas and...

The complexity of the intrarenal renin-angiotensin (Ang) system (RAS) continues to reveal itself as evidence accumulates demonstrating its robust independent regulation in the interstitial and intratubular compartments within the kidney.1–3 Early reports demonstrating the presence of Ang II receptors on the brush border of proximal tubules suggested physiological roles.4 However, because of the...

The murine cell surface protein Crry (complement receptor 1-related protein/gene y) is a key complement regulator with similar activities to human membrane cofactor protein (MCP) and decay-accelerating factor. MCP has a critical role in preventing complement-mediated tissue injury and its mutation has been implicated in several human kidney diseases. The study of Crry in mice has relevance to u...

The movement of Ca2+ across the basolateral plasma membrane was determined in purified preparations of this membrane isolated from rabbit proximal and distal convoluted tubules. The ATP-dependent Ca2+ uptake was present in basolateral membranes from both these tubular segments, but the activity was higher in the distal tubules. A very active Na+/Ca2+ exchange system was also demonstrated in the...

VIEIRA, FRANCISCO LACAZ, AND GERHARD MALNIC Hydrogen ion secretion by rat renal cortical tubules as studied by an antimony microelectrode. Am. J. Physiol. 214(4) : 710-718. 1968.-The pH of proximal and distal tubular fluid of rats on a control diet and of similar rats submitted to 5Cr, NaHC03 or acetazolamide infusions was measured in situ by an antimony microelectrode. The preparation and stan...

Obesity is an independent risk factor for renal dysfunction in patients with CKDs, including diabetic nephropathy, but the mechanism underlying this connection remains unclear. Autophagy is an intracellular degradation system that maintains intracellular homeostasis by removing damaged proteins and organelles, and autophagy insufficiency is associated with the pathogenesis of obesity-related di...

Acute renal failure (ARF) induces tubular hyperresponsiveness to TLR4 ligands, culminating in exaggerated renal cytokine/chemokine production. However, the fate of TLR4 protein during acute tubular injury remains unknown. The study sought new insights into this issue. Male CD-1 mice were subjected to 1) unilateral ischemia-reperfusion (I/R), 2) cisplatin (CP) nephrotoxicity, or 3) glycerol-indu...

Proximal tubular receptor-mediated endocytosis (RME) of filtered proteins prevents proteinuria. Pharmacological and genetic studies in cultured opossum kidney cells have shown that the apical Na(+)/H(+) exchanger isoform 3 (NHE3) supports RME by interference with endosomal pH homeostasis and endocytic fusion events. However, it is not known whether NHE3 also supports proximal tubular RME in viv...

The mechanism of glomerulotubular balance was investigated by microperfusion of the rat proximal tubule at two different rates before and after contriction of the aorta sufficient to produce a 50% reduction in whole kidney filtration rate and plasma flow. At a perfusion rate of 28 nl/min the absolute rate of proximal tubular reabsorption averaged 4.80+/-0.28 nl/mm.min in the absence of aortic c...